upgradeToAggregateIfNeeded(list_of_shapes, types = None): upgrades non-aggregate type
shapes to aggregate-type shapes if the list has a mix of aggregate and non-aggregate
type shapes. Returns the new list. Recursively traverses into compounds.
aggregate shape types are Wire, Shell, CompSolid
non-aggregate shape types are Vertex, Edge, Face, Solid
Compounds are something special: they are recursively traversed to upgrade the
contained shapes.
Examples:
list_of_shapes contains only faces -> nothing happens
list_of_shapes contains faces and shells -> faces are converted to shells
'types' argument is needed for recursive traversal. Do not supply.
References BOPTools.Utils.compoundLeaves().